The "Test and Treat" paradigm has recently emerged as an innovative strategy to address the HIV/AIDS epidemic. This strategy posits that identifying HIV infected individuals through testing and linking them to care to receive prevention services and antiretroviral therapy will both improve health outcomes and reduce HIV transmission at an individual and at a population level. To date, many of the efforts and discussion surrounding this new strategy have focused on addressing increasing HIV testing for the identification of new cases of HIV infection and, to some extent, linkage of new patients to HIV care. However, considerably less attention has been given to retention in care, the critical "fourth component" of the spectrum of engagement in care and an area in which there is great need to develop intervention strategies. Furthermore, retention in HIV care of individuals who are aware of their diagnosis and have never been engaged in HIV care, who are intermittent users of care, or who have dropped out of care also needs to be addressed. A particularly difficult group to retain in HIV care is HIV-infected crack cocaine users. Within this context, this study will test, in a randomized experimental design, if a "Retention Clinic" that provides onsite evidence-based substance use and patient navigation services to HIV-positive crack cocaine users in an HIV primary care setting will improve the HIV care outcomes of HIV-infected crack cocaine users. Our proposed trial will randomize and follow 520 HIV- positive crack cocaine users that either have never been in HIV primary care or have dropped out of HIV primary care over a 12 month period to compare our integrated model's efficacy with treatment as usual. Our specific aims are: 1) To evaluate the efficacy of an integrated care model, the "Retention Clinic", in achieving virologic suppression (defined as having an HIV-1 viral load <400 copies/ml) among HIV-infected crack cocaine users. Additionally, we will also study the efficacy of the "Retention Clinic" in a) increasing attendance at HIV care visits;b) increasing adherence to HIV treatment regimens;c) increasing attendance at substance abuse treatment and, d) decreasing substance use. The proposed approach will represent the first randomized controlled trial of an integrated substance use and patient navigation with HIV primary care for this population. This study is also innovative because there are no proven intervention strategies that address retention to HIV care with HIV-positive crack cocaine users. This study represents a collaboration between the Developmental Center for AIDS Research at the University of Miami and the Center for AIDS Research at Emory University. For the past decade, these two centers have been collaborating on issues related to HIV prevention and access to care for HIV-infected drug users.